1. Field of the Invention
The present invention relates to a method and an apparatus for press casting. More particularly, the present invention relates to a method and an apparatus for press casting for solidifying a molten metal material which is poured into a mold cavity so as to be pressed by a moving mold.
2. Description of the Background Art
There is known apparatus for press casting, which constitutes a mold cavity forming the shape of a cast product with a fixed mold and a moving mold, and solidifies a molten metal material poured into the mold cavity so as to be pressed by the moving mold.
An example of an apparatus for press casting, in which a gate of a molten metal material is provided on a fixed mold; and a cutting-off portion of a molten metal material and a gas exhaust passage are provided on a moving mold, is disclosed in the Japanese Laid-open Patent Publication No. 2005-125401.
However, in the apparatus for press casting as described in Japanese Laid-open Patent Publication No. 2005-125401, it is necessary to form a pouring port, a gas exhaust port and the like for each product mold, and further to incorporate the mechanism for solidifying the molten metal so as to be pressed. Accordingly, such apparatus is likely to cause the increase in size and complication of the apparatus for press casting itself.
Moreover, the apparatus for press casting is unsuitable to relatively small components used for motorcycles and the like. In addition, if it is often requested to change only a part of a mold cavity as in the case of making a plurality of prototypes and the like, it is difficult to respond to such a request with the above-mentioned apparatus for press casting.
The present invention has been made to overcome the drawbacks of the existing apparatus for press casting. Accordingly, it is one of the objects of the present invention to provide a method and apparatus for press casting which is relatively simple, small in size as well as highly versatile, and is capable of pouring, cutting off a molten metal material and exhausting gas efficiently.